simplification of atan(tan(x)), etc



time to introduce another flag? whether to introduce mod expressions?
There was a long discussion of related issues and some papers, in the=20
SIGSAM Bulletin.  The papers used the term "winding number" and
one of the several papers I just found via google:

http://www.inf.uth.gr/~akritas/CE102/p28-corless.pdf

I don't know if this is the best. try google on winding number corless
to get a bunch.

RJF

  ----- Original Message -----

  From: Stavros Macrakis
  To: Robert Dodier
  Cc: Richard Fateman ; Maxima
  Sent: Monday, March 13, 2006 9:26 AM
  Subject: Re: [Maxima] simplification of atan(tan(x)), etc


    > I suggest that atan(tan(x)) not simplify unless  we know -%pi/2 <x =
<%pi/2

    how about atan(tan(x)) => mod (x + %pi/2, %pi) - %pi/2 ?


  I prefer Robert's solution, but agree that it would be nice to have
  something simpler.  Expressions like this appear all the time if you're
  being careful....